Development an application using an object and events language as VBA can reduce the time to programming because it is more intuitive and you can have libraries with procedures. This type of application makes easier to work on the architecture design: it provides information to the architect and guide him in taking the best decision. The time of designing walls considering the acoustical isolation were reduced using a VBA application. The purpose of the present work is to develop an automatic, visual and interactive tool that using a 3D drawing CAD and a object language guide the architect in the design of walls considering the noise from outside and helping the acoustical comfort.